This invention relates to an adjustable shelf device and more particularly to a heavy-duty, wide-span, adjustable shelf device especially suitable for use in the food service industry which substantially minimizes contamination of the shelf adjusting mechanism with food.
An adjustable shelf assembly is very useful. Since shelves are constantly used for storage, adjustability provides for a wide variety of materials of various sizes to be stored at differing times. Such flexibility is extremely useful in any industry. This flexibility of shelf adjustment provides for various sizes of material being stored on the shelves as desired. Variations due to adjustability of shelving achieves these desired results.
Especially in the food industry, adjustability of shelving is desired. It is rarely accurately known whether large or small objects or food containers will need to be stored on a shelf assembly. If these large or small objects can be stored efficiently on shelves adjusted as required, more efficient use of food storage areas can be achieved. Such action is especially valuable in the refrigerated areas. It is very costly to have a refrigerated area improperly used. If the shelves cannot be adjusted for the size of items being refrigerated, proper use of the refrigerated area cannot be accomplished.
Another major problem especially in a food industry is involved with the necessary structure of an adjustable shelf. The adjustable features of the shelf may necessarily provide crevices. Into these crevices, food residue may fall. With the food residue in the crevices, or even caked within the adjustable mechanism of the shelf, great disadvantages occur. It is completely and totally undesirable to have food residue caked in an inaccessible place. Such food eventually spoils--thereby contaminating and rendering the area in general, and the storage device in particular, unsuitable for food storage.
Still another problem with adjustable shelf devices in the food industry is the fact that some of the food cartons stored are extremely heavy--sometimes weighing around 1,000 kilograms. Accordingly, a shelf must be able to hold the weight without deforming the shelf device. If adjustability is also required, another major problem becomes evident. Strength must usually be sacrificed to achieve adjustability. Adjustability weakens the weight holding capability of a shelf. It is extremely desirable to have both strength and weight holding ability together with adjustability--in spite of the inherently countervailing problems therewith.
The National Sanitary Foundation requires any crevices in food storage apparatus to have crevices less than 0.03125 inch (0.079375 centimeter). This requirement mitigates against providing a food storage shelf--both strong enough to support a great weight of food and tight-fitting enough to meet the requirements of the National Sanitary Foundation.
If this unacceptable food collection occurs in a public facility, the facility can be closed and subject to health department sanctions--as well as other business and legal problems. In a home, such a problem can lead to a food-caused illness. It is, therefore, highly desirable to provide an adjustable shelving mechanism which avoids these problems.